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- ID:
- ivo://CDS.VizieR/J/ApJS/201/34
- Title:
- Swift-INTEGRAL X-ray (SIX) survey
- Short Name:
- J/ApJS/201/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The supermassive black holes at the center of active galactic nuclei (AGNs) are surrounded by obscuring matter that can block nuclear radiation. Depending on the amount of blocked radiation, the flux from the AGN can be too faint to be detected by currently flying hard X-ray (above 15keV) missions. At these energies only ~1% of the intensity of the cosmic X-ray background (CXB) can be resolved into point-like sources that are AGNs. In this work, we address the question of undetected sources contributing to the CXB with a very sensitive and new hard X-ray survey: the Swift-INTEGRAL X-ray (SIX) survey, which is obtained with the new approach of combining the Swift/BAT and INTEGRAL/IBIS X-ray observations. We merge the observations of both missions, which enhances the exposure time and reduces systematic uncertainties. As a result, we obtain a new survey over a wide sky area of 6200deg^2^ that is more sensitive than the surveys of Swift/BAT or INTEGRAL/IBIS alone. Our sample comprises 113 sources: 86 AGNs (Seyfert-like and blazars), 5 galaxies, 2 clusters of galaxies, 3 Galactic sources, 3 previously detected unidentified X-ray sources, and 14 unidentified sources. The scientific outcome from the study of the sample has been properly addressed to study the evolution of AGNs at redshift below 0.4.
- ID:
- ivo://CDS.VizieR/J/ApJS/185/433
- Title:
- SWIRE/Chandra survey in Lockman Hole Field
- Short Name:
- J/ApJS/185/433
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a moderate-depth (70ks), contiguous 0.7deg^2^ Chandra survey in the Lockman Hole Field of the Spitzer/SWIRE Legacy Survey coincident with a completed, ultra-deep VLA survey with deep optical and near-infrared imaging in-hand. The primary motivation is to distinguish starburst galaxies and active galactic nuclei (AGNs), including the significant, highly obscured (logN_H_>23) subset. Chandra has detected 775 X-ray sources to a limiting broadband (0.3-8keV) flux ~4x10^-16^erg/cm^2^/s. We present the X-ray catalog, fluxes, hardness ratios, and multi-wavelength fluxes. The logN versus logS agrees with those of previous surveys covering similar flux ranges. The Chandra and Spitzer flux limits are well matched: 771 (99%) of the X-ray sources have infrared (IR) or optical counterparts, and 333 have MIPS 24um detections. There are four optical-only X-ray sources and four with no visible optical/IR counterpart. The very deep (~2.7uJy rms) VLA data yield 251 (>4{sigma}) radio counterparts, 44% of the X-ray sources in the field. More than 40% of the X-ray sources in the VLA field are radio-loud using the classical definition, RL. The majority of these are red and relatively faint in the optical so that the use of RL to select those AGNs with the strongest radio emission becomes questionable. Using the 24um to radio flux ratio (q_24_) instead results in 13 of the 147 AGNs with sufficient data being classified as radio-loud, in good agreement with the ~10% expected for broad-lined AGNs based on optical surveys. We conclude that q_24_ is a more reliable indicator of radio-loudness. Use of RL should be confined to the optically selected type 1 AGN.
- ID:
- ivo://CDS.VizieR/J/ApJS/216/28
- Title:
- SWXCS III. Cluster catalog from 2005-2012 Swift data
- Short Name:
- J/ApJS/216/28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Swift X-ray Cluster Survey (SWXCS) catalog obtained using archival data from the X-ray telescope (XRT) on board the Swift satellite acquired from 2005 February to 2012 November, extending the first release of the SWXCS. The catalog provides positions, soft fluxes, and, when possible, optical counterparts for a flux-limited sample of X-ray group and cluster candidates. We consider the fields with Galactic latitude |b|>20{deg} to avoid high H I column densities. We discard all of the observations targeted at groups or clusters of galaxies, as well as particular extragalactic fields not suitable to search for faint extended sources. We finally select ~3000 useful fields covering a total solid angle of ~400deg^2^. We identify extended source candidates in the soft-band (0.5-2keV) images of these fields using the software EXSdetect, which is specifically calibrated for the XRT data. Extensive simulations are used to evaluate contamination and completeness as a function of the source signal, allowing us to minimize the number of spurious detections and to robustly assess the selection function. Our catalog includes 263 candidate galaxy clusters and groups down to a flux limit of 7x10^-15^erg/cm2/s in the soft band, and the logN-logS is in very good agreement with previous deep X-ray surveys. The final list of sources is cross-correlated with published optical, X-ray, and Sunyaev-Zeldovich catalogs of clusters. We find that 137 sources have been previously identified as clusters in the literature in independent surveys, while 126 are new detections. Currently, we have collected redshift information for 158 sources (60% of the entire sample).
- ID:
- ivo://CDS.VizieR/J/ApJS/186/259
- Title:
- Taurus Spitzer survey: new candidate members
- Short Name:
- J/ApJS/186/259
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the properties of pre-main-sequence objects in the Taurus molecular clouds as observed in seven mid- and far-infrared bands with the Spitzer Space Telescope. There are 215 previously identified members of the Taurus star-forming region in our ~44deg^2^ map; these members exhibit a range of Spitzer colors that we take to define young stars still surrounded by circumstellar dust (noting that ~20% of the bona fide Taurus members exhibit no detectable dust excesses). We looked for new objects in the survey field with similar Spitzer properties, aided by extensive optical, X-ray, and ultraviolet imaging, and found 148 new candidate members of Taurus. We have obtained follow-up spectroscopy for about half the candidate sample, thus far confirming 34 new members, three probable new members, and 10 possible new members, an increase of 15%-20% in Taurus members. Of the objects for which we have spectroscopy, seven are now confirmed extragalactic objects, and one is a background Be star. The remaining 93 candidate objects await additional analysis and/or data to be confirmed or rejected as Taurus members. Most of the new members are Class II M stars and are located along the same cloud filaments as the previously identified Taurus members. Among non-members with Spitzer colors similar to young, dusty stars are evolved Be stars, planetary nebulae, carbon stars, galaxies, and active galactic nuclei.
- ID:
- ivo://CDS.VizieR/IV/39
- Title:
- TESS Input Catalog version 8.2 (TIC v8.2)
- Short Name:
- IV/39
- Date:
- 03 Mar 2022 07:19:26
- Publisher:
- CDS
- Description:
- We define various types of "phantom" stars that may appear in the TESS Input Catalog (TIC), and provide examples and lists of currently known cases. We present a methodology that can be used to check for phantoms around any object of interest in the TIC, and we present an approach for correcting the TIC-reported flux contamination factors accordingly. We checked all 2077 TESS Objects of Interest (TOIs) known as of July 21st 2020 (Sectors 1 to 24) and sent corrections for 291 stars to MAST where they are integrated into the publicly available TIC-8, updating it to TIC 8.1. We used the experience gained to construct an all-sky algorithm searching for "phantoms" which led to 34 million updates integrated into TIC 8.2.
- ID:
- ivo://CDS.VizieR/IV/38
- Title:
- TESS Input Catalog - v8.0 (TIC-8)
- Short Name:
- IV/38
- Date:
- 11 Feb 2022 14:26:27
- Publisher:
- CDS
- Description:
- The TIC is used to help identify two-minute cadence target selection for the Transiting Exoplanet Survey Satellite (TESS) mission, and to calculate physical and observational properties of planet candidates. It is for use by both the TESS science team and the public, and it is periodically updated - the current version is TIC-8. TIC-8 uses the GAIA DR2 catalog as a base and merges a large number of other photometric catalogs, including 2MASS, UCAC4, APASS, SDSS, WISE, etc. There are roughly 1.5 billion stellar and extended sources in TIC-8, containing compiled magnitudes including B, V, u, g, r, i, z, J, H, K, W1-W4, and G. This version was released in May 2019, and is expected to be the last official version of the TIC produced by the TESS mission, although future, independent development of the TIC is possible. The TIC is the responsibility of the SAO Arm of the TESS Science Office under the leadership of David Latham. The TESS Target Selection Working Group (TSWG) is co-chaired by Keivan Stassun (Vanderbilt) & Joshua Pepper (Lehigh).
- ID:
- ivo://CDS.VizieR/I/246
- Title:
- The ACT Reference Catalog
- Short Name:
- I/246
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The U.S. Naval Observatory has completed the compilation of the ACT Reference Catalog, containing 988,758 stars covering the entire sky. The motivation behind the ACT was to provide accurate proper motions for the majority of the stars in the Tycho Catalogue (ESA SP-1200). To do this, positions from new reductions of the Astrographic Catalogue (AC 2000) were combined with those of Tycho. The large epoch span between the two catalogs yields proper motions about an order of magnitude more accurate than those published in the Tycho Catalogue. The astrometric data contained in the ACT Reference Catalog include positions, proper motions and error estimates. These are on the Hipparcos System (J2000.0) for epoch J2000.0. Photometric data (B and V) from Tycho are included. Additionally, cross references to the Tycho, AC 2000, Bonner Durchmusterung (BD), Cordoba Durchmusterung (CD), Cape Durchmusterung (CPD), Henry Draper (HD) and Hipparcos Catalogues are given.
- ID:
- ivo://CDS.VizieR/J/MNRAS/493/2438
- Title:
- The 2BIGB gamma-ray blazars catalog
- Short Name:
- J/MNRAS/493/2438
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the results of a {gamma}-ray likelihood analysis over all the extreme and high synchrotron peak blazars (EHSP and HSP) from the 3HSP catalogue. We investigate 2013 multifrequency positions under the eyes of Fermi Large Area Telescope, considering 11yr of observations in the energy range between 500MeV and 500GeV, which results in 1160 {gamma}-ray signatures detected down to the TS=9 threshold. The detections include 235 additional sources concerning the Fermi Large Area Telescope Fourth Source Catalog (4FGL), all confirmed via high-energy TS (Test Statistic) maps, and represent an improvement of ~25% for the number of EHSP and HSP currently described in {gamma}-rays. We build the {gamma}-ray spectral energy distribution (SED) for all the 1160 2BIGB sources, plot the corresponding {gamma}-ray logN-logS, and measure their total contribution to the extragalactic gamma-ray background, which reaches up to ~33% at 100GeV. Also, we show that the {gamma}-ray detectability improves according to the synchrotron peak flux as represented by the figure of merit parameter, and note that the search for TeV peaked blazars may benefit from considering HSP and EHSP as a whole, instead of EHSPs only. The 2BIGB acronym stands for 'Second Brazil-ICRANet Gamma-ray Blazars' catalogue.
- ID:
- ivo://CDS.VizieR/J/ApJS/195/10
- Title:
- The CDF-S survey: 4Ms source catalogs
- Short Name:
- J/ApJS/195/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present source catalogs for the 4Ms Chandra Deep Field-South (CDF-S), which is the deepest Chandra survey to date and covers an area of 464.5arcmin^2^. We provide a main Chandra source catalog, which contains 740 X-ray sources that are detected with wavdetect at a false-positive probability threshold of 10^-5^ in at least one of three X-ray bands (0.5-8keV, full band; 0.5-2keV, soft band; and 2-8keV, hard band) and also satisfy a binomial-probability source-selection criterion of P<0.004 (i.e., the probability of sources not being real is less than 0.004); this approach is designed to maximize the number of reliable sources detected. A total of 300 main-catalog sources are new compared to the previous 2Ms CDF-S main-catalog sources. We determine X-ray source positions using centroid and matched-filter techniques and obtain a median positional uncertainty of ~0.42". We also provide a supplementary catalog, which consists of 36 sources that are detected with wavdetect at a false-positive probability threshold of 10^-5^, satisfy the condition of 0.004<P<0.1, and have an optical counterpart with R<24. Multiwavelength identifications, basic optical/infrared/radio photometry, and spectroscopic/photometric redshifts are provided for the X-ray sources in the main and supplementary catalogs. Seven hundred sixteen (~97%) of the 740 main-catalog sources have multiwavelength counterparts, with 673 (~94% of 716) having either spectroscopic or photometric redshifts. Basic analyses of the X-ray and multiwavelength properties of the sources indicate that >75% of the main-catalog sources are active galactic nuclei (AGNs); of the 300 new main-catalog sources, about 35% are likely normal and starburst galaxies, reflecting the rise of normal and starburst galaxies at the very faint flux levels uniquely accessible to the 4Ms CDF-S.
